Method for the operation of producer plants



Aug. 2, 1955 w. LINDER ET AL 2,714,670

METHOD FOR THE OPERATION OF PRODUCER PLANTS Filed March 28, 1951 INTERMEDIATE 5 COOLER E E A R GAS TURBINE 76 ELECTRIC LOW PRESSURE GENERATOR COMPRESSOR 7 I HIGH PRESSURE mas? SEPARATOR COMPRESSOR GASlFiER I g/"aze COOLER AND 74 SCRUBBER b" INVENTO RS ALBERT HA'EE HLE W/L LY LIN DE R ATToRNE v United States Patented Aug. 2, 1955 2,714,670 METHoi) non THE oPEnArroN or PRODUCER PLANTS Willy Linder, Essen, and Albert Hilberle, Essen-Warden, Germany, assignors, by mesne assignments, to Koppers Company, lino, Pittsburgh, Pa., a corporation of Delaware Application March 28, E51, Serial No. 217,960 7 Claims. (Ci. 29 9-4) The invention relates broadly to the production of valuable gases which may be utilised for lighting, heating and other purposes and relates in particular to the creased pressure.

It is known in the art increased pressure is advantageous because the solid fuel to be gasified may be chosen of smaller grain size than used in gasifying operation at practically normal pressure.

The disadvantages described above of the gasification of solid fuels at increased pressure are compensated by the similarly increased demand for power necessary to compress the gasifying or blowing air up to the degree which is to be provided in the high pressure gasification apparatus.

It has been proposed to take profit from the energy content of the highly compressed hot gases emerging from the high pressure gasification process by passing them through a waste gas turbine which is working on an air compressor for the production of the gasifying compressed air. The power that may be won from such waste gas turbines is, however, under normal conditions greater than the power requirements of the blowing air compressor. Therefore, it has been proposed to combine the gas turbine in addition to the compressor with an electric power generator. This twofold combination, however, shows a considerable difiiculty during operation, if the power requirement of the electric power generator is diminished for any reason. In this case the waste gas turbine runs away, that is the revolutions per minute of the turbine arise quickly to a degree which may cause heavy destruction in the machine.

A steam driven turbine is easily to be prevented from reac and thus maintaining the revolutions per minute at a preferred value. This is, however, not possible in a turbine equipment which is driven by the useful gas from the gasification process. t is well known that it is impossible to influence or stop the gasification reactions very quickly in order to diminish the amount of gas produced or suppress the production of gas totally. In spite of the fact that the flow of gas froma producer is suddenly cut or valved the gasifying reactions still will continue to produce fuel gas. This fuel gas as prevented from escaping into the main gas line passes the grate of the producer, enters the blowing air line and after mixing with the blowing air forms explosive gas-air-mixtures which when ignited may effect heavy destruction in all parts of the power plant.

It is an object of the invention to overcome these difficulties and to produce a useful gas in a high pressure gasifying process utilising a waste gas turbine in combination with an air compressor equipment and an elecn. um

tric power generator without danger of explosive hazard.

The invention provides such a manner of operation in the said combined high pressure gasifier plant wherein the energy consumption of the waste gas turbine is regulated by means of altering the temperature of the low pressure gas produced in such a way that a sufficient high pressure drop between the gasifier and the main gas line for blowing line.

The invention may be realised Firstly, it is possible to provide a in the main line for the useful ately before the gas escapes from purpose. The throttle valve is to way that the pressure drop of the gas turbine corresponds exactly ment of the energy consuming generator and air compressor) combined with the turbine. In this case the field of regulation of the throt tle valve is to be extended to such a degree, that is to such a pressure drop of the useful gas in the turbine, that the power delivery of the gas turbine may be r duced to the energy requirement of the blowing air compressor.

Another form of realisation of our invention provides a regulable throttle valve in the blowing air feed line of the gasifier.

in both of these cases valving or throttling of the main gas line or the blowing air line respectively effects altering or increasing the temperature of the expanded use ful gas which may be compensated in a very simple mannor by means of a suitable gas cooling system in the useful gas line.

Our invention ensures a complete security of the high pressure producer operation and of the gas turbines so that the said plant may be operated with practically the same security as is known with the usually used steam turbines.

in a manifold manner. regulable throttle valve gas at a place immedithe plant for any other be regulated in such a useful gas in the waste with the power requiremachines (electric power producer operated at increased pressure, a waste gas turbine combined with a blowing air compressor and an electric generator and the throttling means to regulate the energy consumption of the turbine.

-' air with superheated steam which is fed through line 8.

The hot useful gas is passed through the dust separa tor 9 and afterwards reac es the waste gas turbine it) which may be one of the multistage type. By passing the turbine It; the useful gas is expanded and partially cooled down. The gas then flows through line 11., cooler 12, zhich may be constructed as a scrubber, and line 13 to the regulable throttle valve 14 to which the useful gas main line 28 is connected in order to lead the gas to any useful purpose.

The waste gas turbine is coupled with sure compressor 6 which itself pressure compressor the low presis connected to the high 3 by means of a gear Moreover, preferably power genthe shaft of the waste gas turbine 1 .5 is coupled by means of a stageless gear 17 to the electric erator As to be seen from the drawing the temperature of the useful gas produced is easily to be varied by operating the throttle valve equipment 14 in a suitable manner together with the regulating of the cooling or scrubber apparatus 12 which absorbs the surplus of the sensible heat of the useful gas. In this way, the power of energy consumption of the waste gas turbine which is arranged before the throttle valve 14 may be established on a preferred level. It is, however, to be stated that the free path of the gas between the producer and the main gas line will never be shut completely. Moreover, the pressure drop will be maintained in this gas path always at such a degree that a continuous flow of the gas in the direction of the outlet of the main gas line 20 is ensured.

In another mode of realisation of our invention the throttle valve is arranged in the path of the blowing air line 2, as shown at 19, instead of putting it into the line 13. Variations in the t rnperature of the useful gas from the producer caused by the valving effect of the throttle 19 may be compensated by a corresponding cooling effect of the cooler 12 if the power requirement of the waste gas turbine 1.2 is to be reduced similarly.

t should be understood that in addition to each valve being operated separately to control the pressure drop across the turbine, both valves may be operated simultaneously to accomplish the same result. It is, however, to be mentioned that the lines for the useful gas and blowing air respectively in which the valves are provided for are in no case completely closed so that the useful gas produced may escape from the producer in the direction as desired.

As mentioned above it is of advantage to provide for a preferably stageless gear of mechanical or hydrostatic type in order to couple the producer onto the electric power generator. The provision of a stageless gear between the turbine and the electric power generator allows a two or three phase generator to be used in spite of a considerable irregular running of the gas producer.

What we claim is:

1. A method of regulating, in accordance with the load on a gas turbine, the amount of power generated from useful gases by expansion of said useful gases in said gas turbine, said useful gases being produced by the gasification of fuel at increased pressures, said method comprising, gasi'fying a fuel at increased pressures with compressed air to produce useful gases to drive a gas turbine, utilizing the power developed by said turbine to drive other units, regulating the power developed by said turbine in accordance with the load on said turbine by said other units by regulating the pressure differential of the useful gas across said gas turbine, the excess heat in the useful gases after the turbine due to decreasing said pressure differential being absorbed by means of a cooler.

2. The method of claim 1, wherein said pressure differential is regulated by throttling the flow of useful gases exhausting from said turbine.

The method of claim 1 in which the pressure differential is regulated by throttling the flow of compressed air.

4. A method of regulating the speed of a gas turbine to prevent excess turbine speed when loads on units driven by said turbine are reduced, said turbine being powered by power generated from useful gases produced by the gasification of fuel with air at increased pressures comprising, compressing said air in a compressor, flowing the resulting compressed air from said compressor through a compressed air outlet to a gasifrer in which said fuel is gasified by said compressed air at increased pressures to produce useful gases at increased pressures, utilizing the pressure and heat energy of said useful gases to drive a gas turbine which, in turn, drives said compressor and an electric power unit, flowing exhaust useful gases from said turbine through a cooler, regulating the speed of said turbine to prevent excessive turbine speed when the load on said electric power unit is reduced by regulating the pressure differential of the useful gas across said gas turbine, the excess heat present in said exhaust useful gas due to said pressure differential regulation being absorbed in said cooler.

5. The method of claim 4 in which the pressure differential is regulated by throttling the flow of useful gases exhausting from said turbine. I

6. The method of claim 4 in which the pressure differential is regulated by throttling the flow of compressed air to the gasifier.

7. The method of claim 4 in which the pressure differential is regulated by throttling the flow of compressed air to the gasifier and substantially simultaneously throttling the flow of useful gases exhausting from the turbine.

References Cited in the file of this patent UNITED STATES PATENTS 278,255 Nash May 22, 1883 1,486,947 Smith Mar. 4, 1924 1,761,849 Smith June 3, 1930 1,978,837 Forsling Oct. 30, 1934 2,225,311 Lysholm Dec. 17, 1940 2,303,381 New Dec. 1, 1942 2,432,177 Sedille Dec. 9, 1947 2,459,709 Lysholrn Ian. 18, 1949 2,495,604 Salzman Jan. 24, 1950 2,496,407 Pfenninger Feb. 7, 1950 2,558,866 May et al July 3, 1951 2,592,749 Sedille et al Apr. 15, 1952 FOREIGN PATENTS 63,991 Denmark Sept. 17, 1943 66,600 Denmark Apr. 12, 1948 689,581 France May 27, 1930 

